The present invention relates to a pin roll with wedge grooves in the roll body, such wedge grooves being disposed parallel to the axis and serving to accept pinstrips each of which carry a plurality of pins at equally spaced distances. The pinstrips are held fast by clamping wedges acting in the direction of the bottom of the wedge grooves. Pin rolls of this kind are preferably used for drawing mechanisms and combers, but also as stretch pin rolls, perforating rolls, fibrilling rolls, and also as cutting rolls for films.
Pin rolls are already known (for example German DT-OS No. 2 002 020) which hold fast two pinstrips with wedge shaped clamping wedges onto a roll body or a segment of a roll body such pinstrips being each disposed on each side of the clamping wedge. The clamping wedges are fastened to the parent body with screws running approximately parallel to the axis of the wedge so that the wedges press both pinstrips onto the sides of the wedge groove. However, such fastening of the pinstrips cannot be used when the circumference of the roll is occupied by such a large number of pinstrips that the clamping wedges become too narrow to accept any more screw taps.
Other pin rolls are known which have boreholes at definite distances in the direction of the circumference and in the direction created thereby, such boreholes serving as depositories for single pins, such pins being held by pressure onto the end of the shaft. These boreholes may be arranged in such a manner that pins which each follow each other in the direction of the circumference are always disposed in radial planes. This version is extremely expensive, considering the plurality of boreholes in order to obtain the desired density of pins, and on the other hand the limited life of the parent body. Used or damaged pins must be knocked out of the parent body and be replaced by new ones. This process causes an enlargement of the boreholes each time, so that the whole roll becomes unserviceable after some time.
An object of the present invention is to provide an economical solution to this problem and to provide a pin roll which may be provided with clamping wedges for pinstrips even when the strips follow each other very closely and which also may be provided with the pins in radial planes.
According to the present invention of the above described character, each groove is traversed by at least two parallel pegs, and the clamping wedges have oblique slots, disposed in the same direction, which extend from their foot and are traversed by each of the pegs, and the clamping wedges are supported in the longitudinal direction of the wedge grooves in such a manner that they may be held and released by operable means disposed laterally relative to the body of the roll.
Due to the arrangement of the present invention, screws which traverse the clamping wedges become superfluous because action of the wedges is obtained when the clamping wedges are tightened by the cooperation of the pegs, which traverse the wedge grooves, with the respective oblique slots in the clamping wedges, when the clamping wedges are longitudinally displaced. The motions of arresting and of release occur in opposite directions.
In a further embodiment of the invention, a plurality of stop screws are disposed on one side of the roll body, each of these screws engaging the frontal side or longitudinal end of the clamping wedge. These stop screws may be anchored to the roll body in such a way that, depending on the direction in which the screws are turned, the clamping wedges move into the groove or out of the groove. Increasing pressure is exerted upon the pinstrips which abut when the clamping wedges are tightened and when the clamping wedges are lifted, the pressure is released and the pinstrips may be taken out.
It is particularly advantageous when the clamping wedges abut on their opposite frontside onto an adjustable counter element of the rollbody. Each counter element may, in a further embodiment of the present invention, be a setscrew. In this arrangement the stop screws may be used for the tightening of the wedge shaped clamping wedges and in contradistinction, the adjustable counter element may be used in order to lift out the pinstrip, in other words it is actuated against a setscrew.
The pegs, cooperating with the oblique slots of the pinstrips, traverse generally the wedge groove approximately perpendicularly in relation to the centerplane of the wedge groove, such plane passing through the imaginary or real point of the wedge. These pegs may be provided partly with a thread and may be screwed into the body of the body roll.
According to the present invention the body roll is provided with a contact surface for one front side of the pinstrip, and the end of the pinstrip which abuts this contact surface is disposed at a predetermined distance from the center axis of the neighboring outermost pin. Thus, the pinstrip is not arbitrarily cut off, but it ends at an exactly determined distance in relation to the outermost pin of the pin row. Thus every single pin on the circumference of the roll body is not arbitrarily, but exactly positioned. This arrangement, according to the present invention, makes it particularly possible to dispose the pins in individual radial planes, such pins following each other in the direction of the circumference of the pin roll.
It is particularly advantageous to dispose the contact surface abutting onto the roll body in a radial plane of the roll body. The position of each pin is practically unambiguously defined in relation to the roll body when the pinstrips abut onto this contact surface.
It is an object of the present invention to provide that both ends of the pinstrips are also always disposed at a predetermined distance in relation to the center axis of the neighboring outermost pin. These respective distances may be equal as well as different. This construction results in well defined designs of the pin arrangements upon the roll body.
If, for example, the mutual distances between the end of the pinstrip and the middle axis of the neighboring outermost pin amounts to half a pin distance or an odd multiple thereof, the pins of the pinstrips which follow in the direction of the circumferential direction overlap the distance between two pins of the preceding pinstrip, when pinstrips having such differing end distances are arranged alternatingly. Then the pins of alternating pinstrips are staggered. The arrangement of pins in single radial planes makes it also very simple to present two axially parallel disposed rolls to cooperate in such a way that the pins of one roll mesh in their action with the pins of the other roll.
Other features which are considered characteristic of the invention are set forth in the appended claims.
Although the invention is illustrated and described in relationship to specific embodiments, it is nevertheless not intended to be limited to the details shown, since various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims.
The construction and operation of the invention, however, together with additional objects and advantages thereof will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings.